Oscillating piston meter



July 17, 1951 E KAMPF 2,561,280 7 OSCILLATING PISTON METER Filed Dec2'7, 1946 INVENTOR za rrq E H f ATTORNEY Patented July 17, 1 951OSCILLATING PISTON METER Harry E. Kampf, Manhasset, N. Y., assignor toNeptune, Meter Company, a corporation of New Jersey Application December2'7, 1946, Serial No. "718,669

'7 Claims. 1

This invention relates to fluid meters of the oscillating piston type.The invention more particularly relates to an improvement in the meanscooperating with the oscillating piston for preventing leakage of thefluid by the operating parts from the inlet to the outlet of the meter.Oscillating piston meters conventionally are constructed with a casingproviding a cylindrical chamber and a pair of cover plates constitutingwalls of the casing transverse to the axis of the cylindrical chamber.In order to provide for the typical oscillating movement of the pistonin such meters, means are provided for confining a piston of cylindricalform to move so that its axis revolves about the axis of the cylindricalchamber, an edge portion of the cylindrical piston being also confinedto move substantially in a rectilinear path inwardly and outwardlytoward and away from the axis of the cylindrical chamber to produce theconcomitant oscillating movement of the piston. In many conventionaldesigns the means for confining the piston to revolve about the axis ofthe cylindrical chamber takes the form of a body concentric with thecylindrical chamber and providing a cylindrical surface with which aroller or pin carried by the piston engages, A significant feature ofsuch oscillating piston meters also is that a partition is insertedbetween the inlet opening and the outlet opening of the meter whichconventionally extends from the cylindrical wall of the casing towardthe axis and ordinarily abuts a transverse wall between the twoopenings, as well as abutting the central body which provides thecylindrical guide surface, to provide fluid-tight joints with thesecasing walls and with the body to prevent leakage of the fluid by thepartition from the inlet opening to the outlet opening.

In many conventional designs, such as that shown in the patent to C. S.Hazard, No. 1,961,688, June 5, 1934, a slot is cut in the periphery ofthe cylindrical piston and extends toward the axis thereof in the web ofthis piston to provide for cooperation of the piston with the partitionwall to secure the requisite sliding movement of the piston inwardly andoutwardly along the wall. The form of the slot and the provision ofauxiliary devices in some designs are intended to limit so far aspossible leakage past the partition wall. When the parts of such a meterare accurately made a high degree of accuracy of measurement isobtainable because of the peculiar form of the slot which provides forthe oscillating movement by virtue of the combined movement ofrevolution about the axis of the chamber and of translation along thepartition wall. To secure the desired limitation of leakage, however,skill and care are required to produce the requisite fit of the parts.Neverigleless, because of the oscillating movement of the piston, theedges of the slot at the portions thereof which are intended to engagethe faces of the partition must be spaced somewhat so as to provide acertain amount of play. Because of the reciprocating action of thepiston within the casing this play introduces a certain amount of slapwhen reversal of the movement of the piston takes place transversely ofthe partition, bringing one or the other edge of the slot adjacent theperiphery of the piston cylinder suddenly into contact with thecorresponding face of the partition.

In order to reduce the leakage in an oscillatingpiston meter of thistype it has been proposed heretofore, as shown in the patent to Nash,No. 300,628, June 1'1, 1884, to provide a tongue or blade in slidableedge-to-edge contact with the partition, this tongue being pivotallyconnected to the piston so that as the peripheral portion of the pistonmoves along the partition the blade will move in a direction generallyparallel to the partition inwardly and outwardly toward and away fromthe axis of the cylindrical casing. In this device of the prior art,however, although its purpose is to secure a leakage resisting contactof the sliding surfaces no provision has been made to prevent the slapabove referred to due to the play of the piston with respect to thepartition. In this device reliance is placed, as in that of the patentto Hazard, No, 1,961,688 upon the engagement of the edges of the slot atthe periphery of the piston with the face of the partition to providethe guiding movement of the piston inwardly and outwardly as the axisthereof revolves about the axis of the cylindrical casing.

It is an object of the invention to provide an improved means forguiding the oscillating piston of an oscillating piston meter.

It is another object of the invention to provide guiding means for theoscillating piston which will greatly reduce or substantially eliminatethe slap of the piston upon reversal of the movement thereof.

It is another object of the invention to provide for the elimination ofslap concomitantly with improving the resistance to leakage of the fluidby the operating parts between the inlet and outlet openings of themeter.

It is a still further object of the invention to provide an improvedguiding means for an oscillating piston meter capable of beingmanufactured at relatively low cost and requiring only ordinarymanufacturing accuracy.

It is an additional object of the invention to provide such improvedmeans for guiding the piston and for resisting leakage in an oscillatingmeter which is otherwise constructed in conventional form.

It is a feature of the invention that means are provided associated witha blade or tongue slidable in relation to the partition and in relationto the casing for preventing slap and insuring rectilinear movement of aportion of the piston adjacent the circumference thereof along thepartition. The invention utilizes a blade pivotally connected to apiston and oscillatable with respect thereto on an axis fixed inrelation to the piston, the blade being arranged in edge-toedge relationto the partition and for movement substantially in the plane thereof.This blade slidably engages in leakage resisting contact the partitionas well as a wall of the cylindrical casing transverse to the axisthereof. It also engages the cylindrical wall in such leakage resistingcontact. In accordance with the preferred embodiment of the inventionthe blade may be connected to a pivot member of cylindrical form fittingin a cylindrical recess in the piston adjacentthe periphery thereof, theaxis of this cylindrical recess being parallel to the axis Of thecylindrical piston. Leakage of the fluid between the cylindrical .pivotmember substantially is prevented by properly fitting the pivot memberto the recess for pivotal movement therein.

In order to provide for rectilinear movement of the pivot member and thepivotal axis there-- of along the partition, guide shoes are providedconnected to the pivotal member or forming a part thereof and adaptedfor sliding engagement withthe faces of thepartition. These guide shoespreferably are fixed in relation both to the blade and to thecylindrical pivot member, or all these parts may be of unitary form, sothat oscillating movement of the piston on said pivotal axis may takeplace relative to said pivot member, said blade-and said shoes. Thus,the piston may oscillate-with respect to thepivot member and to theguide shoes and to the blade as these parts and the piston move togetherinwardly and outwardly along the partition. As the partition and theparts engaging this partition may be formed with plane surfaces andthese parts may be readily fitted together with the plane surfaces incontact with each other, the cylindrical surfaces fitting in contactwith each other, as above described,such sliding and oscillatingmovements Of the pistonare accomplished without slap and withoutdetrimental leakage of the fluid by the partition and by the cylindricalpivot member and the piston. The fit of the parts in sliding andoscillating relation, however, need not be of *greater' accuracy than isrequisite for the manufacture of the conventional meter. Moreover, theconstruction is such that the parts which are utilized for theimprovement of the invention may be thus manufactured so as to beinterchangeable and if wear occurs replacement may be easily and simplymade to maintain the fit and the accuracy of the meter.

Other objects and features of the invention will appear from thedescription of the drawings to follow.

Fig. 1 shows a plan view of the operating parts withinthe casing of anoscillating meter with a portion of the. piston broken away and with onecover of the casing removed;

Fig. 2 shows a section on line 2-2 of Fig.2;

Fig. '3 shows theblade and guide shoes of the invention with relation tothe partition of an oscillating meter;

Fig. .4'show's a horizontal section of an oscillating r'ne'te'rembodying a modification of the invention;

Fig. is a section on line 5-5 of Fig.4;

Fig. 6 shows'a mcdifiedform of the blade and guid'e'means of theinvention.

In Figs. 1 and 2 is. shown the assembly I of the operating parts of anoscillating meter having'a'cylindrical casing 3 and'covers 5 and 1providing walls transversely of the axis of and fast'enedby suitablemeans to the cylindrical "casing 3. This fastening may be accomplishedby machining or otherwise forming the covers 5 and 1 with shoulderedflanges 9 and H to fit to the casing 3 in fluidtight contact. The cover5 is provided in the conventional manner with a port l3 separated from asecond port l5 by a portion I! of the wall of the cover 5. The ports I3and I5 provide the inlet and outlet openings for the fluid introducedinto the chamber formed by the casing 3 and by the covers 5 and l, whichfluid in its movement from the inlet port to the outlet port impels thecylindrical piston IE] to move with its axis revolving about the axis ofthe cylindrical casing 3 while being guided adjacent the periphery ofthe piston by means, as hereinafter described, to move preferablyradially inwardly toward and outwardly from the axis of the cylindricalcasing 3 to secure the characteristic oscillating movement of the pistonto accomplish the requisite uncovering and covering of the inlet andoutlet ports.

As shown in Fig. 2 a body 2| is fastened to the cover 5 by means ofscrews 23 tapped into the wall of the body 2|. The body 2| preferably isof cylindrical form providing an exterior cylindrical surface 25 and aninterior cylindrical surface 2? concentric therewith. The coincidentaxes of the cylindrical surfaces 25 and 2'! preferably coincide alsowith the axis of the cylindrical casing 3. The cover 5 and the face ofthe body 2| adjacent thereto are finished to provide for fluid-tightcontact of the .body 2| with the cover 5. The annular face 29 of thebody 2| opposite to the cover 5 is formed transversely of and preferablyperpendicular to the common axis of the casing 3 and of the body 2| andis spaced from the inner surface 3| of the cover 1, this surface 3|preferably also being formed perpendicular to the common axis. Thepiston is is provided with a web 33 having parallel surfacesperpendicular to the axis of the piston and in leakage resisting contactwith the annular surface 29 of the body 2| and the inner surface 3| ofthe cover The piston is formed with a wall 35 surrounding a hollow spaceand providing concentric cylindrical "surfaces 47 and 49. The annularsurface 3'! of piston l9 bears against the inner face of the cover 5which is formed perpendicular to the axis of the casing 3.

Fastened in web '33 of the piston |9 concentric with the axis of thispiston in a conventional manner is a stud- 2f projecting axiallyoutwardly to provide for engagement with the registering device of themeter. Fastened in the end wall of the body .21 and in the cover 5 is apin 43 with its axis coinciding with the axis of the casing 3. This pin:33 supports a roller 85 rotatable thereon and of such diameter withrespect to the diameter of the stud M as to be continuously in contactwith the stud 4| as the piston is revolves about the axis of the casing3 and of the pin A 3. The diameters of the external cylindrical surfacell and of the internal cylindrical surface d9 provided by the wall 35 ofthe piston I!) are such that the inner surface 69 bears upon the outersurface '25 of the body 2| as the outer surface ll of the piston bearsupon the inner surface of the cylindrical casing 15 to provide leakageresistingcontact of these surfaces as the piston revolv'es about theaxis of the casing 3. The stud ll, being in contact both with the rollerand the inner surface '27 of the body 2|, maintains the contact of thesurfaces El and A9 of the piston respectively with the'casing 3 and thebody 2| as above mentioned for all positions of the piston IS. Theelements of the fluid meter having an oscillating piston thus fardescribed are of generally conventional form.

The meter of the invention also is provided with a partition 5| which inthe embodiment of Figs. 1 and 2 is fitted in a conventional manner influid tight engagement with a slot or recess 53 in the exterior surfaceof the body 2|. This partition 5| also engages the portion ll of thecover 5,-being fitted fluid-tight in the slot 55.formedin this portionIT. The partition 5| at the edge thereof opposite to the recess 53 alsoengages a slot 5'! in the casing wall 3 in fluid-tight engagementtherewith. The edge 59 of the partition 5| opposite to the recess 55 isparallel to and spaced from the inner surface 3| of the cover 1preferably a distance equal to the thickness of the web 33 of the pistonbetween the surface 3| of the cover 1 and the annularsurface 29 of thebody 2| in order that the inner surface 32 of the web 33' of the pistonmay slidably move in leakage resisting contact with this upper edge 59of the partition 5| as this inner surface of the web 33 slidably moVesin contact with the annular surface 29 of the body 2| in the movement ofthe piston inwardly and outwardly with respect to the axis of thecasing.

To provide against leakage of the fluid between the inlet port and theoutlet port past the partition 5| while at the same time accommodatingfor the inward and outward movement of the piston which produces therequisite oscillation thereof, a blade 6|, which may be of the samethickness as the partition 5| and of the same depth as the thickness ofthe web 33 of the piston, is supported for slidable movement radiallywith respect to the casing 3 inwardly and outwardly along the partitionwith one edge of the blade in contact with the edge surface 59 of thepartition and the other edge of the blade in contact with the innersurface 3| of the cover I. This blade is pivotally supported in thepiston on an axis adjacent the circumferential surface 41 thereof. Inthe embodiment of Figs. 1 and 2 a cylindrical pivot member 63 isrotatably fitted into a cylindrical recess 65 formed in the wall 35 ofthe piston with the axis of the cylindrical recess parallel to the axisof the piston. The pivot member 63 is fastened to or formed as part ofthe blade 6| so that this blade and pivot member as a unit may pivotallymove in the cylindrical recess relative to the piston l9. It will beapparent, therefore, that as the piston moves to revolve its axis aboutthe axis of the cylindrical casing 3 the piston also may oscillate withrespect to the cylindrical pivot member 53 and the blade 6| if thisblade is confined to move along the length of the partition 5| andthereby to move the pivotal axis of the blade and the portion of thepiston in which the axis is positioned radially inwardly and outwardlytoward and away from the axis of the cylindrical casing to secure thecharacteristic action of the oscillating piston meter.

In order to secure the requisite radial movement of the pivotal axis oraxis of oscillation of the piston along the partition 5| the pivotalmember 63 15 provided with guide shoes or legs 61 which extendtransversely of the blade 6| and provide contact surfaces in the shoes6! slidably engaging the faces of the partition 5|. In the particularembodiment of Figs. 1 and 2 the legs 61 are shown as extensions of thecylindrical pivot member 63 providing therebetween a slot containing theaxis of the pivotal member and extending from the free ends of theselegs toward and to meet the surface of the blade 6| which makes contactwith the surface 59 of the partition 5|. The inner end of this slot isformed as a continuation of this contact surface of the blade 6| so asto maintain the leakage resisting contact of the blade and of thepivotal member 63 with the upper surface 59 of the partition in allpositions of the blade and pivotal member along the partition. In theparticular embodiment of Figs. 1 and 2 also the blade 5| passes througha slot 69 formed in the casing 3 to provide leakage resisting contact ofthe blade 5| with this casing wall. The blade 6| is of such length as toextend into the slot 69 to afford such contact with the casing wall whenthe pivot member 63 is in the position at the end of its movementadjacent the cylindrical body 2|. When this pivotal member is attheopposite end of its movement it will be apparent the blade.

willzproject outwardly of. the casing 3. The parts shown in Figs. 1 and2 ordinarily are con,- tained within an exterior meter body which may besuitably designed to provide room for the projection of the blade 6|. 1

In order to accommodate the oscillating move,- ment of the piston ISwith respect to the cylindrical pivot member 63 and the-shoesB'Iextending therefrom and to avoid interfering with the full movementof the inner surface 49 of the piston I9 into contact with the exteriorsurface 25 of the body 2| as the piston reaches the end of its movementinwardly along the partition,

the cylindrical surfaces of the pivot member 63 and of the shoes 61 aretruncated as shown at H in Fig. 3. Similarly, these cylindricalsurfacesare truncated at 12 and 13 as shown in Fig. 3 at either side ofthe blade 6| in order to. avoidinterference with the full movement ofthe exterior surface 4'! of the piston l9 into contact with the innersurface of the cylindrical casing.

3 when the piston moves outwardly along the partition 5|. Thistruncation of the pivot member 53 and the shoes 61 in this particularembodiment is necessary because the diameter of the pivot member and ofthe shoes is greater than the thickness of the wall 35 of the piston.Such provision may be necessary inaccommodating the device of theinvention to oscillating meters of conventional construction in whichthe thickness of the cylinder walls 35 is not sufficientto accommodate apivot member having a diameter large enough to provide a good bearingsurface in the cylindrical recess 65 for the cylindrical member 63 and,as well, to provide substantial thickness for the legs or shoes 61 andadequate fiat bearing surfaces in these shoesfor contact with the facesof the partition 5|.

In the embodiment of the invention illustrated in Figs. 4, 5 and 6 theconstruction is generally similar to that of Figs. 1 and 2, like partscarrying like reference numerals. bodiment, however, the piston I9 isformed with the wall 35 thereof of greater thickness than that of theembodiment of Figs. 1 and 2, this. thickness in this particularembodiment being substantially equal to the diameter of the pivot member15 of cylindrical form which is pivotally supported in a cylindricalrecess 11 formed in the wall 35 of the piston l9. In the embodiment ofFigs. 4, 5 and 6 the partition 5| extends from the recess 53 in thecentral body 2| through the wall of casing 3 without making contact withthis wall. The outer end of the partition 5| is fitted in a recess 19provided in the wall of a bulge 8| In this em- 2,5131 ,aeo

formedupon the exterior of the casing 3.. The

partition 5|, as in the embodiment :of. Figs- 1.

and 2, engages a recesstE in the .portion ill of the cover 5; this coverhaving a portion B3 extending outwardly to. cover. the chamber enclosedby thewall of. the bulge 8!. The cover I also has aportionst whichextends outwardly to cover this chamber oppositelyto the: portion 33- ofthe cover a.

The embodiment ofFigs. 4 and 5 utilizesa combined blade and guidememberfll, Fig. 6,.in which the blade may be formed integrally with.thepi-vot.

member 15 and withguide shoes 89 extending downwardly from the blade .88for thefull length.

of the blade outwardly from the pivot member 1'5. Between the shoes 89thereis 'providedsa slot 91 extending fully through the member 81parallel to the blade 88 and inthe plane of the.

axis of the pivot member 15. Theinner faces. of the shoes 89 are spaced.apartby thisslotso as to bear in contactwith the faces'ofithepartition5l for the full extent of the length. of the blade 88 to guidethe guide member and'the blade and the pivotimemberfor.movementinthe'plane of the partition 5|. The length of the .partition 51 and theextent of the bulge 8| outwardly from "the casing 3 are such thatwhenthe piston is moved to the position in which the pivotal member 15 isadjacent the wall of the casing 3 the end. of the blade 88 and the endedges of thei-sho'es. 89 project almost to but do. not reach the; wallof the bulge 81. blade 88 and of the shoes89 along the partition also issuch that the end edges of these members do. not pass within the casing3 when the piston moves inwardly of the casing and the pivotalmember I5is'adjacent the cylindrical body 21. It will be apparent that the blade88 and the pivotal axis of the pivot member 15 are guided forrectilinear movement along the partition 51. Asthis axis is positionedin the wall 35 of the pieton Hi this portion of the wall 35' is givenrectilinear movement inwardly and outwardly of the axis of the casing 3between the extreme positions of the piston. The shoes 89 being ofsubstantial extent lengthwise of the partition to insure the rectilinear.m'ovement of the axis of. the pivotal member 75 also insure thecorrect" kinematic action of theyperipheral portion of the piston tosecure the requisite oscillation thereof as-the axis of the pistonrevolves about theaxis of the cylindrical casing 3 without play or lost.

motion between the cooperating parts.

In order to accommodate :for the oscillating movement of the pistonrelative to the guide member 81' the wall 35 of the-piston is relievedslightlyat. both the inner cylindrical surface and the outer cylindricalsurface thereof, as shown in Fig.

4- adjacent' the. surface of the. cylindrical. recess H. It will beunderstood that only such relief is necessary as to prevent engagementof the edge of the piston wall with the partition '5l I or with the.outer surface of .theshoesv 89 as the piston oscillates in. its movementwithin the. casing '3.

It will be understood that the upper surface 93. of the blade 8-8, Figs.5 and 6, moves in. sliding.v

leakage resisting contact with the under face of the cover I in the samemanner as described'inconnection with Figs. 1 and 2, the under surface950i this blade similarly making contact with the upper edge surface 59of the partition 51.

The. wall 3, as shown in Fig. 4-, provides an open-' ing' 91 for passagetherethrough of the member.

81. The edges of the wallat the opening-91 are formed to bear. againstshoes 89 to provide. leakage resisting contact therewith. It will beunderstood, since the shoes:

89 cooperating with thexpartition '51 serve to guide the .pivot'inember15; that is, theaxis thereof which iswpositioned in thewa'll '35 of thepiston-19 inwardly and outwardly in theplane of the partition, that is;radially of the. casing, that. the wall 3 of the casing is not requiredtov serve.

forguiding the blade :as is the case in'the embodiment of Figs 1 and 2.The contact of theshoes 89 with the edges of the casing wall 3 servesmerely to prevent leakage of the fluid into the chamber of the bulge 8|where it may pass-around the-edge of'thepartition. While-in thepreferred embodiment this contact may be. accomplished by fitting of:the surfaces of the shoes. which ordinarily would be made of metal, tothe-metallic wallv of the casing,,-within.the

1 :scope of the invention, if desired, other means for preventingleakage between the shoes and the casing maybe adopted.

The operation of thefi uid meter of the invention isqgenerally the sameas that of conventional mete-rs. The 'iluid entering through one of theports, for example the port it, fills thechamber at the left of thepiston in Fig. :1 and'at the .left of partition 5! and of the blade illcooperating therewith in the position of the piston as shownin thisfigure. As the outlet port 15' is uncovered by the piston the fluid inthechamber formed within the casing at the right of the piston and atthe right of the partition 51 and of the blade BI be discharged. throughthe opening t5. The pressure attire left of the piston is effective tomove the oscillating piston, that is, the'axis ofthe stud 4lin thecounterclockwise direction about the axis of the casing and of thepinl3. Thus, in Fig. 1 the pivotal member 63 and the peripheral portion ofthe piston have started to move outwardly along the partition and suchmovement will continue until the outer circumference of the-pistonsubstantially is tangent to the inner cylindrioal'surface of the wall 3of the casing adjacent the partition.

When the piston has reached this uppermost positionxin Fig. litheinletjport l3 communicates.

with the space within the piston and the inner surface of the wall 35bears upon the 'outerzsurface of thebodyfil toprevent passage ofthe'fiuid.

to the outlet port 5.5. The fluid pressure acting at the inside of thepiston between the wall 35 thereof and the-body 21 will causethe pistonto pivet'on-the pivotal'member 6-3 swinging towardthe left in Fig. -l.,the stud l-l continuing to movecounterclockwise about the axis of thepin 4.3.

This pressure "continues .to act as .the piston :is.

moved-downwardly until the port l3 again is .uncovered at the'outer sideof the piston. Theepress sure of the fluid then is brought upon-theoutside ofithe piston .to continue the movement. The port l5; thenbecomes uncovered at the 'insideof the piston for discharge ofthefluidwithin the piston through this outlet port. The-fluid at the.outside ofithev piston previously admitted through the port isdischarged-through the part I 5 as the pistoncontinues-'itsmovementthrough the position shown .in-l ifl. 'luntil :the piston again :is

in upper tangent position.

it will apparent from the above description that the invention providessimple :means -forpre venting leakage past the partition, utilizingpreferably devices which maybe-machined by ordinary methods to --cylindrical and plane surfaces for securing the-leakage resistingcontact ofsuhthe. .outer faces of the surfaces where relative movement therebetweensecure the proper fit of the surface of the blade BI and the edgesurface 59. Not only is the essential resistance to leakage thus securedbut the undesirable and in many cases detrimental action which resultsin slap of the piston upon reversal thereof is avoided by virtue of theimproved oscillating axis guiding means of the invention.

Within the scope of the invention the form and construction of thisunitary element which provides the pivot, the leakage preventing bladeand the guide shoes may be varied while retaining the essential featuresof securing rectilinear move- -ment of the pivotal axis along thepartition, that is the movement of the axis of oscillation of the pistonfor correct kinematic action thereof within the casing, concomitantlywith providing against leakage of the fluid by the partition from .theinlet of the meter to the outlet thereof. The

unitary element of the invention is adapted'to be made of differentmaterials suitable to the purpose for which the meter is designed andfor low cost of manufacture with accuracy consistent with the accuracyof the conventional parts of the oscillatingpiston meter to which theinvention is applicable. All such variations and modifications of theinvention are intended to be within the scope of the claims appendedhereto.

The term oscillating piston as used in the claims designates a membersupported within a casingfor revolution of a central point thereof aboutan axis of revolution, a point adjacent the periphery of the memberbeing confined concomitantly to move in reciprocating movement inwardlytoward and outwardly away from the axis of revolution.

I claim:

1. In a fluid meter, the combination with a casing providing a chamberhaving a cylindrical wall and a wall transversely of said cylindricalwall, a cylindrical oscillating piston within said chamber, means forconfining said piston for movement of the axis thereof about the axis ofthe cylindrical chamber while maintaining said axes parallel and thecircumference of the piston in contact With said cylindrical wall of thecasing, said casing having in said wall thereof transverse to the axisof the cylindrical chamber a fluid inlet opening and a fluid outletopening spaced ciroumferentially about the axis of said cylindricalchamber, and a partition extending from said cylindrical wall of saidchamber toward the axis thereof and abutting said transverse wall andcooperating with said confining means and said transverse wall toprovide substantially fluid tight joints therewith, of a bladesupportedfor movement thereof substantially in the plane of said partitioninwardly and outwardly toward and away from the axis of said cylindricalchamber, said blade cooperating with said partition and with atransverse Wall of said casing to provide leakage-resisting contacttherewith, a pivot member rigidly connected to said blade for engagingsaid piston adjacent the circumference thereof for pivotal movement ofsaid piston with respect to said blade, and means rigidly connected tosaid blade adjacent the pivotal axis of said 10 pivot member'andengaging said partition for guiding said pivotal axis and said piston tomove inwardly and outwardly along said partition as the axis of thecylinder of said piston is moved about the axis of said cylindricalchamber.

2. In a fluid meter, the combination with a casing providing a chamberhaving a cylindrical wall and a wall transversely of said cylindricalwall, a cylindrical oscillating piston within said chamber, a bodyWithin said chamber providing a cylindrical surface concentric with theaxis of said cylindrical. chamber, means carried by said piston andengaging said cylindrical surface of said body for confining said pistonfor circular movementof the axis thereof about and in parallel relationto the axis of said cylindrical chamber and with the circumference ofthe piston in contact with said cylindrical wall of the casing, saidcasing having in said wall thereof transverse to the axis of thecylindrical chamber a fluid inlet opening and a fluid outlet openingspaced circumferentially about the axis of said cylindrical chamber, anda partition extending from said cylindrical wall of said chambertoward'the axis thereof and abutting said body and said transverse wallbetween said inlet and said outlet openings and cooperating with saidbody and said walls to provide substantially fluid tight jointstherewith, of a pivot member pivotally engaging said piston upon apivotal axis fixed in relation to and adjacent the circumference of saidpiston an parallel to the axis of the cylinder thereof, guiding shoesrigidly connected to said pivot member at either side of the pivotalaxis thereof and adapted for sliding engagement with th faces of saidpartition to provide for movement of said pivot member and of saidpiston along said partition'toward and away from the axis of saidchamber upon movement of the axis of the cylinder of said piston aboutthe axis of said cylindrical chamber, and a blade rigidly connected tosaid pivot member with the plane of the blade substantially in the planeof said partition and in edge-toedge relation thereto for movement ofsaid blade with said pivot member and said guiding shoes along saidpartition, said blade coopcrating with said partition and said. casingto provide lealrage-resisting contacts therewith to prevent leakage offluid by said partition from said inlet opening to said outlet opening.

3. In a fluid meter, the combination with a casing providing a chamberhaving a cylindrical wall and closing Walls transversely of saidcylindrical wall, a cylindrical oscillating piston within said chamber,a body within said chamber providing a cylindrical surfaceconcentricwith the .axis of said cylindrical chamber, means carried faceof said body for confining said piston for circular movement of the axisthereof about and in parallel relation to the axis of said cylindricalchamber and with the circumference of the piston in contact with saidcylindrical wall of the casing, said casing having in a wall thereoftransverse to the axis of the cylindrical chamber a fluid inlet openingand a fluid outlet opening positioned adjacent said cylindrical wall ofsaid casing and spaced circumferentially about the axis of saidcylindrical chamber, and a partition extending from said cylindricalwall of said chamber toward the axis thereof and abutting said body andsaid transverse wall between said inlet and outlet openings of said walland cooperating with said body and said cylindrical casing wall and saidtransverse wall to provide substantially fluid .tight joints therewith,said-cylindrical oscillating piston having a web transverse-to the sideof said pivotal axis thereof extending in the direction from said webtoward said transverse wall of said casing in which said inlet and saidoutlet openings are formed and adapted for sliding engagement with thefaces of said partition to provide for movement of said pivot memberandv of said, piston along said partition toward and away from the axisof said chamber concomitantly with oscillating movement of said pistonrelative to said pivot member upon movement of the axis of the cylinderof said piston about the axis of said cylindrical chamber, and a bladerigidly connected to said pivot member with the plane of the bladesubstantially in the plane of said partition in edge-to-edge slidingrelation thereto and in'leakage-resisting contact therewith for movementthereof along said partition together with said pivot member and saidpiston,

said blade also engaging in sliding relation and in leakage-resistingcontact both the transverse wall of said casing opposite to that inwhich said openings are formed and the cylindrical wall of said casingsubstantially to'prevent leakage of the fluid by said partition fromsaid inlet opening to said outlet opening.

4. In a fluid meter the combination as defined in" claim 3 in which saidcylindrical piston is formed with a peripheral wall providing acylindrical exterior surface for contact with said cylindrical casingwall and an internal cylindrical surface for engaging the cylindricalsurface of said body, said cylindrical pivot member being of greaterdiameter than the thickness of said peripheral wall of said piston andbeing truncated to provide a surface extending generally parallel to theaxis thereof to prevent substantial interference with the contact of thecylindrical wall surfaces of the piston respectively with thecylindrical wall surfaces of the casing and of the cylindrical bodywithin the chamber provided by the casing.

5. In a fluid meter the combination as defined in claim 2' in which saidguiding shoes extend from said blade in face-to-face relation with saidpartition at either side thereof for a substantial part of the length ofsaid blade, the outer faces of said guiding shoes being adapted tocooperate with the cylindrical casing wall to provide leakage resistingcontact therewith.

6. In a fluid meter, the combination with a casing having a peripheralwall and having inlet and outlet openings for the fluid flowingtherethrough, an oscillating piston within said casing adapted torevolve about an axis of revolution concomitantly with oscillationthereof, and means including a partition between said inlet and saidoutlet openings extending in the direction from said peripheral wall ofsaid casing toward said axis of revolution and cooperating with said casing to prevent leakage of fluid past said partition from said inletopening to said outlet opening, of a unitary member providing a bladeadapted to move along said partition inwardly and outwardly with respectto said axis of revolution and to prevent leakage past said cylindricalportion and said partition in the movement;- of said unitary member andsaid blade along said partition, the parts of said cylindrical portionof said unitary member at either side of said slot being adaptedslidably to engage the faces of said partition for guiding-said unitarymember. along saidpartition, said oscillating piston being formed withaperipheral wallextending about, said axis ofrevolution of said pistonand being provided with a cylindrical recess adjacent said peripheral,wall having the axis thereof parallel to said. axis of revolution ofsaid piston, said recess being adaptedt'o receive said, cylindricalportion of said unitary member to provide for-pivotal movement of saidpiston with respect to said unitary member, where-by in the revolutionof said piston about said axis of revolution within the casing. theaxisof said recess and the peripheral portion of said piston adjacentthereto are guided to move inwardly andoutwardly along said partitionconconiitantly with oscillation of said piston upon saidaxis of saidrecess.

7.. In a fluid meter, the, combination as defined in claim 3 inwhichsaid cylindrical piston is formed with a peripheral wall providing acylindrical exterior surface for contact with'said cylindrical casingwall and a concentric interior cylindrical surface for engaging thecylindrical surface of said body, said cylindrical pivot memberproviding a cylindrical bearing surf-ace in contact with cooperatingcylindrical surfaces of said recess of substantial extentwhich areformed in said peripheral wall of said piston at opposite sides of thepivotal axis of said pivot member to provide for the pivotal movement ofsaid piston withrespect to said pivot member, saidperipheral wall havinga thickness relative to the diameter of said cylindrical pivotmember andthe axis of saidpivotmember being located in said peripheral wall so asto preventcontact ofsaid cylindri'cai pivot member with said casing walland with said cylindrical body surface in the movement of said pistonand, said blade along said partition, said peripheral wall adjacentsaid' contacting bearing surfaces of said cylindrical pivot member andsaid recess being relieved to provide for said' pivotal movement ofsaidv peripheral wall relative to said blade.

HARRY E. KAMPF.

REFERENCES CITED The following references are of record, in, the file ofthis patent:

UNITED STATES PATENTS Number Name Date 380,628 Nash June 17, 18841,631,687 McLane Dec, 16, 1913 1,856,850 Mardcn May 3, 1932 2,455,628Ulrich Dec. 7-, 19 .8 2,462,063 Berg-man Feb. 22, 1949

